Although not limited in its scope or applicability, the present invention relates generally to a device used with an endoscope, and more particularly the device that may be used, by way of illustration and not by way of limitation, for delivery of medication and/or for taking a biopsy of a lesion, tumor, neoplasm or other object of, for example, a biliary tree that includes bile ducts, cystic ducts, hepatic ducts, common bile duct, pancreatic ducts, and other channels associated therewith.
Bile Duct
Bile is a fluid made in the liver and then concentrated and stored in the gallbladder, which is a pear-shaped organ found below the liver. Bile helps with digesting fat in the small intestine. The way that bile moves from the liver to the intestine is via a bile duct.
In general terms, the bile duct is a tube about 4 to 5 inches long in the average adult that connects the liver, gallbladder, and pancreas to the small intestine, the part of the digestive tract that is located between the stomach and the large intestine. In more specific terms, the bile duct is sometimes known as a biliary tree (a network of bile duct tubes, cystic ducts, hepatic ducts, common bile duct, pancreatic ducts, and other channels associated therewith). The bile duct begins in the liver as many small channels that gather bile from the liver cells. These small channels all join into one tube (the hepatic duct). About one-third along the length of the bile duct, the gallbladder is attached thereto by a small duct called the cystic duct. The combined duct is called the common bile duct. The end of this part of the bile duct is what empties into the earliest part of the small intestine, next to where the pancreatic duct also enters the small intestine.
At times, problems may develop within the bile duct, whereby bile duct exploration becomes a necessary medical procedure. One example of bile duct exploration is a procedure used to see if a stone or some other obstruction is blocking the flow of bile from the liver and gallbladder to the small intestine. This can cause bile to back up into the liver and result in jaundice or infections, which may require emergency surgery to remove the stone or blockage.
Another example of bile duct exploration is with diagnosing the bile duct, bile duct neoplasms, and bile duct tumors for cancer. Bile duct cancer can develop in any part of the bile duct and, based on its location, is typically divided into three groups. About two-thirds of bile duct cancers develop at the part of the hepatic duct where the bile ducts have joined and are just leaving the liver. These are called perihilar cancers and sometimes Klatskin tumors. About one-fourth of bile duct cancers are found in the common bile duct nearest the intestine. These are called distal bile duct cancers. Rounding out the remaining percentage of bile duct cancers is the third group, which includes cancers that develop in the small bile duct branches inside the liver and are called intrahepatic (i.e., inside the liver) bile duct cancers.
Not all bile duct tumors are cancerous. For instance, bile duct hamartomas and bile duct adenomas are benign tumors. Once the patient presents with symptoms, however, bile duct tumors typically require a prognosis to determine whether they are cancerous or benign. For instance, a physician or other healthcare professional (collectively, “physician”) may conduct a history and a physical examination to check for signs of disease, such as lumps, jaundice, and anything else that seems unusual. The physician may also perform liver function tests, in which a blood sample is checked to measure the amounts of certain substances released in the blood by the liver. Another procedure involves the use of a CT scan, whereby a dye is injected into a vein or swallowed to help the organs and tissues show up more clearly in pictures made by a computer that is linked to an X-ray machine. An MRI (magnetic resonance imaging) is still another procedure. This procedure uses a magnet, radio waves, and a computer to make a series of pictures of areas inside the body. Two other examples include the use of ultrasound and biopsy.
Ultrasound
Ultrasound is a familiar medical procedure and is commonly used, for example, in obstetrics and gynecology. Ultrasound utilizes transducers, often called probes that both generate and receive high-energy sound waves (ultrasound) with the use of quartz crystals by utilizing a principle called the piezoelectric effect. When the crystals receive an electric current, the crystals change shape and produce the high-energy sound waves that travel outward to the tissue. Conversely, when sound or pressure waves bounce off internal tissues or organs (make echoes) they hit the crystals, which then emit electrical currents. Therefore, the same crystals can be used to send and receive sound waves. A central processing unit processes the electrical currents emitted by the crystals as a result of the echoes, and the echo patterns are shown on a screen of an ultrasound machine to form a computer picture of body tissues called a sonogram.
Biopsy
Biopsy is the removal of cells or tissues for examination so they can be viewed under a microscope to check for signs of cancer. When a physician removes only a sample of tissue, then the procedure is known as an incisional biopsy or core biopsy. When the physician removes an entire lump or a large area, then the procedure is known as an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is known as a needle biopsy or fine-needle aspiration.
In a fine-needle aspiration procedure, a fine sterile needle is inserted into the bile duct and guided, typically by employing ultrasound technology, to the tumor location for biopsy. Aspiration is a suction process that removes the cells or tissue sample to be examined under a microscope.
The types of needles that physicians commonly use for biliary aspiration biopsy are a long beveled needle, a ball-tipped needle, or a dimpled needle. Each of these needles is constructed in the axial direction from a relatively homogenous material. In other words, each needle may be made of a substantially consistent composition or material along the length of the needle. For example, the entire needle may be formed of the same material, such as surgical stainless steel or similar alloy. Because of the tortuous paths that the needle must navigate, it would be desirable to have a device comprising a needle with additional flexibility at its distal end, as taught herein.